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1.
对2010年1月—2016年7月重庆市中毒救治指定医疗机构收治的2 497例中毒患者进行回顾性分析。结果显示,中毒患者中男性1 230例(49.3%)、女性1 267例(50.7%);分布最多的3个年龄段依次是41~50岁(18.5%)、≤10岁(16.4%)和21~30岁(13.0%);死亡16例,病死率0.6%。中毒类型构成排前三位的是细菌(33.8%)、化学品(32.2%)、植物(14.8%)。中毒预后多因素Logistic回归分析结果显示重度中毒患者结局死亡的可能性是轻度患者的1 102倍。提示重庆市应重点关注农村地区41~50岁人群的细菌、化学品、药物中毒,同时应该加强儿童中毒防控工作。  相似文献   
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目的 :建立聚合酶链反应 (PCR)方法检测谷胱甘肽 S转移酶 (GST) M1基因 ,并探讨 GST M1基因缺失 (无效基因型 )与喉癌易患性的相关性。方法 :观察组选择确诊的喉癌 4 2例 ,正常对照组 10 8例 ;取被检者外周静脉血白细胞 ,抽提制备脱氧核糖核苷酸 (DNA) ;选择优化后的 PCR反应体系和循环参数扩增 GSTM1,扩增后的基因产物用 2 %琼脂糖凝胶电泳 ,紫外线灯下观察并记录结果。结果 :(1)成功建立聚合酶链反应结合琼脂糖凝胶电泳技术检测 GSTM1基因的方法。(2 )喉癌组 GST M1基因缺失率 (71.4 % )明显高于正常对照组 (48.1% )显示两组之间差异存在显著性 (χ2 =6 .6 1,P<0 .0 5 )。结论 :(1)聚合酶链反应是一种简单敏感 ,准确可靠的分析 GST M1基因多态性的方法。 (2 )该地区 GST M1基因缺失与喉癌的易患性相关联  相似文献   
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This 1-year (September 2000 to August 2001) prospective study investigated the presence of hepatitis A virus (HAV) in the population of Monastir, Tunisia (86 serum samples), in the influents and effluents of two wastewater treatment plants, and in shellfish harvested in the coastal areas of Monastir, Bizerte and Sfax (January 2001 to May 2001). The virus was detected by RT-PCR using primers targeted at the VP3-VP1 region. An epidemic of HAV infection was observed during the winter months, with a peak in January. The presence of the virus was relatively constant in the influents and effluents of the wastewater treatment plants, and the virus was found in shellfish from the Monastir area during the months of January and February. The genotype IA strain was recovered most frequently from human serum and wastewater samples. The observation that the peak of the epidemic was during the winter months suggests that transmission of HAV is related to climatic factors and, presumably, to shellfish consumption.  相似文献   
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Thirty-eight Swedish patients with chronic hepatitis C were randomly assigned to receive either 3 million units (MU) or 5MU of human lymphoblastoid interferon-α-n1 (Wellferon) three times per week for either 6 or 12 months. The patients were monitored biochemically, histologically and by quantitative polymerase chain reaction for circulating HCV RNA, during therapy and for the following year. Overall, 22 (58%) of the patients lost detectable hepatitis C virus (HCV) viraemia during therapy but eight of these patients relapsed during follow-up, leaving 14 (37%) sustained responders. Patients infected with HCV non-type 1 genotypes were significantly more likely to achieve a sustained response than were those infected with HCV type 1 (63% vs 10.5%, P =0.001). Sustained virological responses were also associated with lower pretreatment viraemia level, younger age, absence of cirrhosis and the higher interferon dosage regimens but these associations failed to reach statistical significance. In 97% of patients there was concordance between virological and biochemical responses, and a statistically significant ( P =0.005) improvement in the Knodell histological activity index was observed in the virological sustained responders.  相似文献   
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Male mice, genetically selected for differences in brain weight or from a heterogeneous (HET) stock, were used to explore potential interactions between genotype and exposure to lead as manifested in activity. At the time of birth dams and their pups were given either water or a 0.5% lead acetate solution as the sole source of fluid. Fluid conditions remained constant throughout the experiment. The effects of chronic lead on activity in young adult mice depended on the genotype of the individual. Specifically, in an open field, HET mice exposed to lead tended to be more active than their control counterparts. Low-and high-brain weight lead-exposed mice at times were hypoactive but this effect depended on the specific nature of the measure.This research was supported in part by National Science Foundation Grant DAR7911233 to Peter J. Donovick and Richard G. Bruggight and by Biomedical Research Support Group Grant 5S077RR07149 to Peter J. Donovick.  相似文献   
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The clinical relevance of hepatitis B virus (HBV) genotypes has been documented; however, the prevalence of mixed HBV genotype infections in at-risk groups remains controversial. The HBV genotypes were determined in 325 HBV-infected intravenous drug users (IVDU) who were at a greater risk of multiple exposures to different HBV genotypes by using a newly developed line probe assay. The distribution of HBV genotype was as follows: genotype A alone in 2 (0.6%); genotype B alone in 256 (78.8%); genotype C alone in 10 (3.1%); mixed genotype A and B in 18 (5.5%); genotype B and C in 30 (9.2%); genotype B and D in 1 (0.3%); genotype A and C in 1 (0.3%); and mixed infections of genotype A, B, and C in 3 (0.9%). Clonal analysis confirmed further the existence of mixed genotype infection and recombination between different genotypes. Compared with our previous data, the line probe assay seemed more sensitive than polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) assay in identifying HBV genotype (98.8% vs. 65.0%) and detecting mixed genotype infections (16.3% vs. 0%). In conclusion, the prevalence of mixed HBV infections is substantially higher in IVDU in endemic areas, and the line probe assay is a useful method for rapid genotyping of HBV, with particular reference to the detection of mixed genotype infections.  相似文献   
8.
Clinical recurrences of Herpes simplex virus type 1 (HSV-1)-associated genital herpes are thought to be caused by reactivation of latent endogenous HSV-1. However, the possibility of reinfection with exogenous HSV-1 cannot be excluded. This study aimed to determine the incidence of genital HSV-1 superinfection in patients by investigating the genotype of sequential HSV-1 isolates obtained from the same anatomical site of patients with clinical recurrences of genital HSV-1 recurrent genital herpes. Sequential genital HSV-1 isolates were genotyped by PCR amplification of the hypervariable regions located within the HSV-1 genes US1 and US12. Whereas the sequential HSV-1 isolates in 11 of the 13 patients studied had the same genotypes, the sequential isolates of 2 patients showed a different genotype. The data suggest that HSV-1-induced recurrent genital herpes can be associated with genital reinfection with an exogenous HSV-1 strain.  相似文献   
9.
The pathogenic mechanisms that lead to chronic hepatitis C are unknown. As hepatitis C virus (HCV) has been shown to induce T cell response, we assessed whether a particular T lymphocyte subset could be preferentially detected in the liver of patients with chronic hepatitis C in relation to viraemia or HCV genotypes. The immunophenotypes of liver-derived lymphocytes were analysed in 26 patients by flow cytometry and immunohistochemistry. Viraemia was quantified by branched DNA assay. Using this assay, HCV RNA was not detectable in six patients. HCV RNA was detected in 20 patients, and titres ranged from 8 to 137 x 10(6) Eq/ml. Genotyping was performed using a line probe assay. Type 1a, 1b, 2a, 3a and 4a were found to infect 2, 10, 2, 7 and 3 patients, respectively. The CD4+/CD8+ ratio of liver-derived lymphocytes was significantly higher (P < 0.01) in patients with detectable viraemia than in patients without detectable viraemia. In contrast, neither the percentage of gamma/delta T lymphocytes nor that of CD2+CD57+ cells was different in the groups. When comparing the CD4+/CD8+ ratio, the percentage of gamma/delta T lymphocytes or CD2+CD57+ cells according to genotype, the differences were not significant. These results suggest that the CD4+/CD8+ ratio of liver-derived lymphocytes is related to viraemia but not to HCV genotypes in patients with chronic hepatitis C, and that T lymphocytes may be involved in the pathogenesis of liver lesions in chronic hepatitis C.  相似文献   
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The TT virus (TTV) load was estimated in sera obtained from 237 patients with hepatitis C virus (HCV)-related chronic liver disease including 42 patients with hepatocellular carcinoma (HCC), by real-time detection PCR using primers and a probe derived from the well-conserved untranslated region of the TTV genome, which can detect all known TTV genotypes. Of the 237 patients studied, 18 (8%) were negative for TTV DNA, 87 (37%) had low TTV viremia (1.3 x 10(2)-9.9 x 10(3) copies/ml), and 132 (56%) had high TTV viremia (1.0 x 10(4)-2.1 x 10(6) copies/ml). Various features were compared between the patients with high TTV load (n = 132) and those with no TTV viremia or low viral load (n = 105). High TTV viremia (> or =10(4) copies/ml) was significantly associated with higher age (P < 0.05), past history of blood transfusion (P < 0.001), complication of cirrhosis (P < 0.05) or HCC (P < 0.0005), lower HCV RNA titer (P < 0.05), and lower platelet count (P < 0.01). On multivariate logistic regression analysis, high TTV viral load was a significant risk factor for HCC (P < 0.05), independent from known risk factors such as complication of liver cirrhosis (P < 0.0001) and high age (> or =65 years, P < 0.05), among all 237 patients. Furthermore, high TTV viral load was an independent risk factor for HCC among the 90 cirrhotic patients (P < 0.05). These results suggest that a high TTV viral load is associated independently with the complication of HCC and may have prognostic significance in patients with HCV-related chronic liver disease, although whether high TTV viremia mediates the progression of HCV-related chronic liver disease remains to be defined.  相似文献   
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